var orgin={age:100};
function Person(){

}
Person.prototype=orign;
var attr={value:'john1',configurable:false,
enumerable:false};//json
var attr1={value:'john1',configurable:true};//json
Object.defineProperty(person,"name",attr);
//Object.defineProperty(person,"name",attr1);
//person.name="tom";
delete person.name;
console.log(person.name);
for(var p in person){
	console.log(p);
}